Back when it was just a scrappy little startup instead of a social networking juggernaut, Facebook's motto used to be "move fast and break things." Of course, when you serve 1.2 billion people across the planet—many of whom are prone to totally flipping their wigs at any little design change—breaking things by moving fast isn't quite as appealing. The new motto seems to be "move slow, and don't mess anything up." What has changed is mostly a matter of refinement.

This would go a long way to explain why Facebook took just one day short of a full calendar year to unveil a news feed redesign that is, in effect, pretty subtle. It's cleaner, the images are bigger, and Facebook has replaced the default fonts with Helvetica and Arial, two extremely ubiquitous sans-serif typefaces. That's pretty much it, but it's all in service of a mobile-first design mentality that is slowly but surely taking over the world's largest social network.

Currently rolling out in stages to Facebook users internationally, the news feed update is essentially just a skin job on top of the old feed. There are no behind-the-scenes changes with regard to how content or ads are surfaced; the navigation and layout remains the same. What has changed is mostly a matter of refinement. The new motto seems to be 'move slow, and don't mess anything up.'

In the new design, everything is cleaner, bringing the desktop Facebook experience in line with the mobile experience. Label icons have been updated to a more modern style, closer in line to the icons used in Facebook's apps. Tappable buttons replace text links in many interface elements, like "Add Friend" dialogues. The "Sort" interface, which allows users to choose which News Feed they want to see, has been moved to the left-hand menu bar. Images and linked content thumbnails are also bigger, because the news feed no longer wastes a strip of vertical whitespace that was previously solely devoted to user profile pictures. Now, images can take up the full width of the central news feed column, making them slightly bigger than they were before.

For type aficionados, perhaps the most glaring design change of the new news feed is that Facebook has switched fonts, from defaults of Lucida Grande on Mac and Tahoma on Windows, to Helvetica on Mac and Arial on Windows. It's an odd move, given that just two months ago, Facebook was experimenting with highly ornamental, newspaper-style headlines, about as far away stylistically as you can get from Arial and Helvetica. The stated rationale of this change is that Facebook was looking for something that felt more "like a system font," according to what Facebook's Greg Marra told Techcrunch. A system font is one of the fonts that ships with an operating system, and used as default in the user interface. Maybe Facebook will look more like Paper in 2020.

This is a curious statement, because Lucida Grande and Tahoma were system fonts, but on desktops, not on mobile devices, where Helvetica and Arial are more popular. The wording, subtle though it may be, implies that Facebook has truly embraced a mobile-first mentality, a theory backed up by the fact that, in every other sense, the new news feed has primarily been overhauled to make it look more like Facebook's apps, which is what Mark Zuckerberg said the point of this redesign was when it was first previewed a year ago.

It will be worth watching to see if this trend continues. In the future, could the news feed borrow design cues from Paper, Facebook's beautiful new iPhone app? Given how long it took Facebook to pull the trigger on this news feed redesign, maybe by 2020.

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